In the related art, a forced air-cooled cabinet includes one or more functional plug-in boxes and one or more air deflection plug-in boxes, which are alternately stacked. Heating electronic components and fans arranged at top ends or bottom ends of the functional plug-in boxes are mounted in each functional plug-in box. An air deflection diaphragm, which divides each air deflection plug-in box into two areas, is arranged in each air deflection plug-in box, an area on one side of the air deflection diaphragm is a channel for sucking cold air suction passage of one functional plug-in box, and an area on the other side is a channel for exhausting hot air of another functional plug-in box. Along with increase of functions of the functional plug-in boxes, heat power consumption increases. The air deflection diaphragm is baked by hot air exhausted by the functional plug-in box on one side of the air deflection diaphragm, which causes high temperature of the air deflection diaphragm, thereby heating air on the other side of the air deflection diaphragm and make a functional plug-in box on the other side of the air deflection diaphragm to suck heated air to cause a poor radiation effect of the functional plug-in box on the other side of the air deflection diaphragm.